Serena Williams was rushed to Cedars-Sinai Medical Center in Los Angeles on Monday for a blood clot in her lungs, according to People.

Williams' rep said her client suffered a pulmonary embolism last week, and she was hospitalized for "a hematoma suffered as a result of treatment for a more critical situation." Her rep added, "Doctors are continuing to monitor her situation closely to avoid additional complications."

Last night the 29-year-old tennis star tweeted, "Tough day..." and she also responded to BFF Kim Kardashian's excitement over her new music video, so it sounds like she's on the road to recovery.